1. Field of the Invention
This invention relates to the field of fiber optics, and in particular to an adhesiveless fiber optic connector, an apparatus for facilitating termination of a fiber optic cable to an adhesiveless fiber optic connector, and a method of terminating a fiber optic cable to an adhesiveless fiber optic connector.
2. Discussion of Related Art
Light energy generated by a broadband source and modulated to carry information is commonly transmitted by fiber optic systems using fiber optic cables and connectors. Typically, a fiber optic system begins with a source such as a laser which generates a light energy signal and injects it into an optical fiber. The signal travels through the system via a series of optical fibers which are connected in end-to-end fashion by connection assemblies. Each connection assembly is made up of a fiber optic connector attached to or terminated to the end of an optical fiber, and an adapter which receives the ends of the connectors and precisely aligns the optical fibers in the connectors in abutting, end-to-end relationship.
In order to minimize attenuation of the signal as it passes from the optical fiber in one connector to an optical fiber in the adjoining connector, it is imperative that the optical fibers in the connectors be positioned so that they are precisely aligned when the connectors are connected to one another via the adapter. In view of external forces and environmental stresses which are applied to the connectors it is necessary to securely fix the optical fiber within the connector so as to avoid drift or displacement which results in misalignment of the optical fiber when connected in a connection assembly.
A variety of techniques have been proposed to secure an optical fiber of a fiber optic cable within an optical fiber connector. One common method is to inject an adhesive, such as an epoxy, into the connector to fill the space between the optical fiber and the inner surface of the connector. When the adhesive is cured, the optical fiber is held securely in position within the connector.
While adhesives provide good retention of the optical fiber within the connector, they suffer from the disadvantages of being difficult to apply with precision and of requiring time to cure before the optical fiber is held securely. These disadvantages are especially serious for applications where the cable cannot be removed from an installation and in situ termination of the cable to a new connector is necessary.
To avoid the use of adhesives, U.S. Pat. No. 5,088,804, the disclosure of which is hereby incorporated by reference, describes an optical fiber connector which utilizes a deformable, elastomeric material placed within the connector to surround the optical fiber. When the connector is assembled with an optical fiber, the elastomeric material is compressed inwardly around the optical fiber to secure it in position.
Alternatively, U.S. Pat. No. 4,812,006, the disclosure of which is hereby incorporated by reference, discloses an adhesiveless retention mechanism for an optical fiber cable connector which utilizes a compressible collet which, when fully inserted in the connector, is compressed inwardly and clamps against the outside of the fiber optic cable.
In addition, U.S. Pat. No. 5,140,662, the disclosure of which is hereby incorporated by reference, discloses an adhesiveless retention arrangement in which the main body of the connector is crimped directly to the cable, eliminating any sort of collet or separate retention arrangement.
While effectively eliminating the need for adhesives, the elastomeric retention and collet retention techniques of the type described in the above-cited patents, as well as other known techniques for securing optical fiber within connectors without the need for adhesives, have a number of disadvantages. These disadvantages generally include decreased stability relative to adhesive-based arrangements, and/or relative complexity. Even where adequate resistance to drift is achieved, the problem of aligning the relatively small optical fibers with openings in the connector, while at the same time manipulating the termination arrangements, requires at least a high level of skill or training, and makes field installation difficult.